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create_checkout

Purchase a catalog SKU using available account credit, otherwise start Stripe Checkout. Prefer create_inbound_number for a fax number. sku: credit_pack | inbound_30day | monthly-basic | annual-basic | monthly-business | annual-business | lifetime-basic | lifetime-pro. HIPAA/EIN/IRS are website-only (list_skus). Do not use this to send a document. Use create_fax_draft.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "sku": "<sku>"
    },
    "name": "create_checkout"
  }
}

Input Schema

Name	Required	Description	Default
`sku`	Yes
`state`	No
`country`	No
`amountCents`	No

Output Schema

Name	Required	Description	Default
`sku`	Yes
`notes`	No
`status`	Yes
`orderId`	No
`websiteUrl`	No
`checkoutUrl`	No
`creditCents`	No
`phoneNumber`	No

Schema Changelog

Changes observed during successful MCP inspections.

Changed1 schema field changedOct 7, 2026

changedOutput schema / properties / status / enum

Previous value: -[
-  "awaiting_payment",
-  "website_only"
-]New value: +[
+  "awaiting_payment",
+  "website_only",
+  "provisioning"
+]

Changed11 schema fields changedSep 13, 2026

addedInput schema / $schema

Added value: +"https://json-schema.org/draft/2020-12/schema"

removedInput schema / additionalProperties
```
Removed value: -false
```

removedInput schema / properties / amountCents / description

Removed value: -"credit_pack only. Defaults to 2000 ($20). Minimum 50."

addedInput schema / properties / amountCents / maximum
```
Added value: +9007199254740991
```
addedInput schema / properties / amountCents / minimum
```
Added value: +50
```

removedInput schema / properties / country / description

Removed value: -"US or CA for number SKUs (default US)"

addedInput schema / properties / country / enum
```
Added value: +[
+  "US",
+  "CA"
+]
```

removedInput schema / properties / sku / description

Removed value: -"credit_pack | inbound_30day | monthly-basic | annual-basic | monthly-business | annual-business | lifetime-basic | lifetime-pro"

addedInput schema / properties / sku / enum

Added value: +[
+  "credit_pack",
+  "inbound_30day",
+  "monthly-basic",
+  "annual-basic",
+  "monthly-business",
+  "annual-business",
+  "lifetime-basic",
+  "lifetime-pro"
+]

removedInput schema / properties / state / description

Removed value: -"Optional US state or CA province for number SKUs"

changedOutput schema / (root)

Previous value: -nullNew value: +{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "additionalProperties": false,
+  "properties": {
+    "checkoutUrl": {
+      "type": "string"
+    },
+    "creditCents": {
+      "type": "number"
+    },
+    "notes": {
+      "type": "string"
+    },
+    "orderId": {
+      "type": "string"
+    },
+    "phoneNumber": {
+      "type": "string"
+    },
+    "sku": {
+      "type": "string"
+    },
+    "status": {
+      "enum": [
+        "awaiting_payment",
+        "website_only"
+      ],
+      "type": "string"
+    },
+    "websiteUrl": {
+      "type": "string"
+    }
+  },
+  "required": [
+    "status",
+    "sku"
+  ],
+  "type": "object"
+}

AddedSep 3, 2026

TDQS

A4.1/5.0

Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations only declare it is a non-read-only, open-world, non-destructive call. The description adds real behavioral context beyond that: it silently prefers available account credit and only falls back to Stripe Checkout otherwise, which materially affects the outcome. It does not cover auth requirements, idempotency, or the credit-vs-card failure path, keeping it short of a 5.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loads the core action, then terse routing and exclusion notes; every sentence carries routing or restriction value. The inline sku value list is somewhat redundant with the schema enum and inflates length without adding meaning.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

An output schema exists, so return values need no explanation, and the destructive/read-only profile is covered by annotations. However, for a purchase tool with an open-world payment side effect, the description omits the semantics of the three optional parameters and says nothing about failure or refund behavior.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters2/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0%, so the description must carry the parameter burden. It only restates the sku enum values (already in the schema) and says nothing about state, country, or amountCents — notably amountCents' role in credit-pack purchases and country/state's role in tax or Stripe routing is left entirely unexplained.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource — purchase a catalog SKU — plus the payment mechanism (account credit, falling back to Stripe Checkout). It explicitly distinguishes itself from create_inbound_number and create_fax_draft, so an agent can route without opening sibling schemas.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives explicit alternatives with the conditions that select them: create_inbound_number for a fax number, create_fax_draft for sending documents. It also lists exclusions (HIPAA/EIN/IRS are website-only via list_skus), which is exactly the when-not guidance an agent needs.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

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